Proposal for a simple synthesis prognostic staging system in chronic myelogenous leukemia.
OBJECTIVE
Several prognostic models or staging systems have been published that identify different risk groups in patients with Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML). The aims of this study were (1) to test, in an independent population, the prognostic reproducibility of these staging systems; and (2) to develop a synthesis staging system that could be easily applied in clinical practice.


METHODS
A total of 406 patients with newly diagnosed Ph-positive CML were evaluated by the four published staging systems of Tura, Cervantes, Sokal, and our group. The proposed synthesis staging system was developed based on the most consistent prognostic characteristics, and the presence or absence of accelerated disease features at diagnosis. The staging systems were compared according to survival outcome, as well as by looking for differences of survival outcomes within a specific stage of a defined system, when patients in this stage were subclassified by a second staging system.


RESULTS
Whereas the staging system of Cervantes et al identified only two prognostic groups (median survivals of 49 versus 40 months; p = 0.01), the remaining three staging systems were able to segregate patients into stage 1, 2, and 3 risk groups with respective median survivals of 56 to 57, 41 to 42, and 28 to 36 months, respectively (p less than 0.001 to p less than 0.002). The new proposed staging system, based on the existence of zero to one (stage 1), two (stage 2), or three or more unfavorable (stage 3) characteristics, or the presence of accelerated disease features (stage 4), categorized patients into four prognostic groups with median survivals of 56, 45, 30, and 30 months, respectively (p less than 0.001), the latter stage (stage 4) being associated with a higher one-year mortality rate (29%). The synthesis staging system was also able to subclassify patients within most of Tura's and Sokal's stages into significantly different prognostic groups by survival outcome.


CONCLUSIONS
The predictive prognostic capacity of three of the four published staging systems was confirmed in this independent or test population. The new proposed staging system was superior to the staging systems of Tura and Sokal in identifying different prognostic subgroups.
Kantarjian
H M
HM
Department of Hematology, M.D. Anderson Cancer Center, Houston, Texas.
Keating
M J
MJ
Smith
T L
TL
Talpaz
M
M
McCredie
K B
KB
D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D009367:Neoplasm Staging / Q000379:methods*; D010677:Philadelphia Chromosome; D011379:Prognosis